Depression and anxiety are common symptoms among people with Irritable Bowel Syndrome (IBS). A study out of India suggests that probiotic supplementation may improve these symptoms among those with IBS.

Adults who ingested a probiotic supplement daily for 90 days reported a significant improvement in several self-assessment questionnaires of depression symptoms and quality of life compared to those who ingested a placebo.

The study, published recently​​ in the journal Food & Nutrition Research,​ was funded and conducted by Sabinsa Corporation/Sami Labs Limited, a manufacturer of dietary ingredients, which includes the studied probiotic strain Bacillus coagulans ​MTC 5856 (branded as LactoSpore) in its portfolio.

According to a press release from the company, the idea to explore the strain’s potential in depressive symptoms came after its president Shaheen Majeed noticed depression to be commonly reported among study participants with IBS at the time of screening for the first clinical trial conducted on LactoSpore​​, which primarily looked at safety of supplementation and gut health changes post supplementation.

Gut-brain axis​

“Recent pre-clinical and clinical research reveals that the human microbiota plays a pivotal role in cognitive and affective functioning,” ​the authors wrote, adding that their results adds to the body of evidence that probiotic supplementation may act as an adjuvant therapy for depression.

In addition to questionnaire results, the Sabinsa study also measured levels of myeloperoxidase (or MPO), a cellular enzymes responsible for the production of free radicals which leads to the cellular oxidative stress.

“By considering the clinical importance of MPO and its clinical relation with IBS and depression, we investigated the serum level of MPO in this study,” ​they wrote.

“[We found] a significant decrease in ​B. coagulans MTCC 5856 receiving patients from the baseline at the end of the study, unlike the placebo group.”​

A specific mechanism of action, however, remains to be confirmed. One suggestion is that the probiotics may be producing certain neurotransmitters, hormones, and immune- and neuropeptides and short-chain fatty acids, which help alleviate depression symptoms.

Study details​

Forty adults participated in the study at three different healthcare sites in Bangalore, India. The clinical trial took place between June 2015 and October 2015.

All participants were newly diagnosed, which means no other treatment to alleviate their depression or IBS symptoms had been done.

They were randomized into two groups, and in a blinded-manner, were given either a probiotic tablet or placebo. They ingested the tablets at least 30 minutes before a meal in the morning for a period of 90 days.